Means of preparing a fuel-air mixture

ABSTRACT

A means and method wherein a portion of an air supply is diverted, subject to intense turbulence, then injected into a fuel supply to create a turbulent fuel-air premixture which is immediately introduced into the air supply. Further included in some embodiments is a means of producing mechanical vibration in parts located in the region wherein premixing occurs, and in the region wherein introduction of the premixture into the main air supply occurs.

United States Patent 1151 3,685,808 Bodai 14 1 Aug. 22,1972

[ MEANS OF PREPARING A FUELeAlR 2,014,907 9/1935 Myers ..261/79 RMIXTURE 2,273,979 2/1942 Mock ..261/1 3,539,157 11/1970 Fort.;....26l/DlG. 69 [72] Invent 3,519,407 7/1970 Hilbom .,..261/D1G. 39[73] Assignee: Technoscience Systems, Inc., La

p m C l ii FOREIGN PATENTS OR APPLICATIONS 22 i July 23 1970 389,7856/1921 Germany ..261/79 R [21] Appl 57,524 Primary ExaminerTim R. MilesAttorney-Lyon & Lyon [52] US. Cl. ..261/1, 261/79 R, 261/121 A,

261/D1G. 39, 259/D1G. 43 ABSTRACT lnt. A means and wherein a v v port1onof an an [58] held of Search D 6 2; supply is diverted, subject tointense turbulence, then I injected into a fuelsupply .to create aturbulent fuelair premixture which is immediately introduced, into [56]References Cited the air supply. Further included in some embodimentsUNITED STATES PATENTS is a means of producing mechanical vibration inparts 3 located 1n the region wherem premixlng occurs, and in 1,729,3829/1929 Harel "26I/DIG- 39 the region wherein introduction of thepremixture into 3,332,231 7/1967 Walsh ..261/79 R the main air SupplyOccm 7 2,453,595 ll/1948 Rosenthal ..261/1 1,752,506 4/1930 Portail..261/79 R 7 Claims, 13 Drawing Figures PA'Ti'mimuszz m2 SHEET 1 OF 2INVENTOR. [EA B40 )4. 500m MEANS OF PREPARING A FUEL-AIR MIXTUREBACKGROUND OF THE INVENTION It is well established that the efficiencywith which a fuel-air mixture may react and, hence, the amount ofcontaminants in the residue is related to the degree and character ofthe intermixture of fuel and air prior to reaction. More specifically,in the operation of internal combustion engines, it has long beenrecognized that improved performance'and reduction of pollutants can beattained if the fuel and air or either component is subjected to sonicor ultrasonic vibrations or turbulence.

Attempts have been made to accomplish this by utilizing piezoelectriccrystals exposed to either or both combustion components; however, thecost is high and the efficiency is low due to the problem of effectivetransfer of energy from the crystal to the component.

Also, attempts have been made to. utilize acoustical means to producethe desired vibrations or turbulence in one or both components. Anexample of this ap proach is shown in U.S. Pat. No. 2,532,554, in whicha version of the I-Iartmann supersonic generator is used. This hasrequired the use of air under pressure, and hence, the use of acompressor; even then, the effect seems to have been minimal, foralthough this approach to the problem has been available for many years,it has never come into use.

Also, for many years, an acoustical device known as a vortex whistle hasbeen known. An example is a paper presented by Vonnegut in the Journalof Acoustical Society of America, Volume 26, No. l, in January of 1954.Again, although this approach has been known for many years, it has notcome into general use, and in the few cases where the vortex whistle hasbeen adopted, the resulting structure seems to have been too expensiveand complicated for incorporation in the fuel supply systems of internalcombustion engines.

SUMMARY OF THE INVENTION The present invention is directed to a means ofpreparing a fuel-air mixture which overcomes the problems heretoforeencountered and is summarized in the following objects:

First, to provide a means of preparing a fuel-air mixture wherein aportion of an air stream is diverted, subjected to intense turbulence,then injected into a fuel supply to create a turbulent fuel-airpremixture which is immediately introduced into the air supply.

Second, to provide a means, as indicated in the preceding object, inwhich an adaption of a vortex whistle is utilized to generate turbulentvibrations which are not merely effective to break up liquid fuel intosmaller droplets, but apparently produces an unstable foam comprisingair particles surrounded by a film of fuel which rapidly disintegrateswhen exposed to the main air supply to form an intimate extremely finelydivided fuel mixture therewith.

Third, to provide a means, as indicated in the other objects, which isparticularly adapted to supply combustion components to internalcombustion engines and wherein the vortex whistle is operated by apressure differential established within the main air passage or barrelof a carburetor.

Fourth, to provide a means, as indicated in the other objects, which mayutilize a conventional carburetor modified to incorporate a novellyarranged vortex whistle, or a plurality of vortex whistles if thecarburetor is provided with more than one barrel, with the result thatimproved engine performance may be accomplished at minimum expense.

Fifth, to provide a means, as indicated in the other objects, whereinthe vortex whistle discharges across a fuel passage and impinges againsta reflecting and focusing surface to intensify the turbulence in theregion of initial mixture with the fuel.

Sixth, to provide a means, as indicated in the other objects, whichutilizes the diverted air stream to produce mechanical vibration ofparts exposed to the fuel in the region wherein premixture occurs and inthe region wherein introduction of the premixture into the main airsupply occurs.

Seventh, to provide a means, as indicated in the preceding object,wherein the mechanical vibration of the parts is produced by rotation ofa solid mass in the vortex whistle chamber.

DESCRIPTION OF THE DRAWINGS FIG. 1 is an enlarged fragmentary sectionview of a conventional carburetor which has'been modified toincorporate, the means for preparing the fuel-air mixture.

FIG. 2 is a fragmentary plan view, taken from 22 of FIG. 1.

FIG. 3 is an enlarged fragmentary sectional view, taken through 3-3 ofFIG. 2.

FIG. 4 is a partial plan, partial sectional view, taken through 4-4 ofFIG. 3.

FIG. 5 is a fragmentary sectional view, similar to FIG. 3, illustratinga modified construction.

F IG. 6 is an enlarged transverse sectional view, similar to FIG. 4,taken through 6-6 of FIG.-7, showing a modified construction.

FIG. 7 is a longitudinal sectional view, taken through 7-7 of FIG. 6.

FIG. 8 is a transverse sectional view, corresponding to FIG. 6, showinga further modification.

FIG. 9 is a further enlarged fragmentary sectional view, showing amodified wall of the vortex chamber.

FIG. 10 is a transverse sectional view of a further modification, takenthrough 10l0 of FIG. 1 1.

FIG. 11 is a longitudinal sectional view, taken through 11-11 of FIG.10.

FIG. 12 is a fragmentary sectional view of a carburetor, correspondingto FIG. 1, showing a modified construction. g

FIG. 13 is a fragmentary plan view, corresponding to FIG. 2, but takenfrom 1313 of FIG. 12.

The present invention may be incorporated in an otherwise conventionalcarburetor, if the resulting fuel mixture is intended for an internalcombustion engine. The carburetor, designated 1, is provided with one ormore barrels or main air passages 2. In each passage is centered aventuri tube 3, supported in place by a radially extending fuel supplytube 4. The supply tube intersects an annular distributing passage 5,located within the venturi tube 3, and having ports 6 which intersectthe venturi passage 7 in its region of smallest diameter, this being thezone'or region having the minimum pressure; that is, a pressure lowerthan the normal pressure of the air flowing in the passage 2.

1 boss 8, on which is mounted a vortex whistle unit 9. The vortexwhistle unit includes a body 10, of circular configuration, having astem 1 1 press fitted in or otherwise secured in the boss 8. The stem 11forms an outlet passage 12 from the vortex whistle unit which intersectsthe passage formed within the fuel supply tube 4.

The body 10 forms a cylindrical vortex chamber 13 at the upper end ofthe passage 12, the vortex chamber being substantially larger than theoutlet passage. The upper end of the vortex chamber is closed by a cap14.

The upper portion of the vortex chamber ,is surrounded by a wall 15 ofreduced thickness, and immediately below the cap 14 thewall 15 isprovided with one or more tangential inlet ports 16. In the constructionillustrated, two inlet ports are provided, but an additional number maybe used if desired. The body 10 receives a deflector ring 17, whichprojects upwardly in spaced relation to the reduced wall 15, and itsinner surface converges upwardly.

The method of preparing a fuel-air mixture utilizing the carburetor andthe vortex whistle is as follows:

A conventional throttle valve, not shown, is located below the venturitube 3. Variation in position of the 1 throttle valve determines theamount of air which flows downwardly through the passage 2. A portion ofthe air determined by the size of the deflector ring I 17 is diverted tothe inlet ports 16 and on entering the ports is caused to form a vortexwithin the chamber 13.The vortex is intensified by its reduction indiameter as it flows outwardly through the passage 12. The airdischarging from the outlet passage 12 impinges upon liquid fuel flowingthrough the supply tube 4, and the resulting premixture flows into theannular distributing passage for discharge through the ports 6 into theventuri passage 7. t

The force which produces this movement of the air diverted from the main.body of air flowing in the passage 2 is derived fromtwo.complementarysources.

First, the air on impinging against the upper end of the body and thesurrounding deflector ring 17 increases in pressure with respect to thenormal pressure of the air flowing in the passage2. Second, the venturipassage produces a pressure which is' lower than the pressure of themain body of air. As a result, the-pressure differential is sufficientto create a turbulent vortex within the chamber 13. This vortex isintensified and rendered more turbulent as it enters the outlet passage12. This is due to the fact that as the radius of rotation is reduced,.the speed of rotation increases. The air which discharges from thepassage 12 is highly turbulent and undergoes intensive vibration withthe result that it immediately reacts with the liquid fuel 18 in thesupply tube 4. to produce an unstable and intimate intermixture of airand fuel. It is believed that the resulting mixture is in the form of anunstable froth or foam, comprising air particles surrounded by extremelythin membranes of fuel in a liquid state. in any case, the highlyagitated mixture passes rapidly fromthe point of initial mixture to thepoints of discharge through the ports 6 into the venturi passage 7.Whether or not there is actually transient stage in which an actualfroth exists, the particles of liquid which enter the venturi tube arematerially smaller than the particles normally received in the venturitube of a conventional carburetor.

Tests have established the fact that when the construction hereinbeforedescribed is substituted for a fully conventional carburetor, a materialreduction in carbon monoxide output is attained. Byway of example, anautomobile having a carbon monoxide output in the order of 5 per centunder conventional conditions shows a carbon monoxide output too smallto obtain a reading on a carbon monoxide meter.

One series of tests involved the use of a new carburetor installed in alate model automobile. Performance tests were first made of thecarburetor without modification, as follows:

1. Under idling condition, the carbon monoxide output (CO) was nominal,approximately 0.2 percent.

2. Under steady state conditions, with the vehicle in motion andstationary, and with partially openthrottle representing speeds in therange between 25 and 35 miles-per-hour, the exhaust discharge *a'veragedapproximately 2.5 percent CO. Y

3. Under steady state high speed conditions,

representing freeway travel in the range between 60 and miles-per-hour,the exhaust discharge averaged V approximately 1.0 percent CO. e

4. Under conditions of rapid throttle acceleration and deceleration,with the vehicle in motion or stationary, the CO content increasedsubstantially, to the range between 5 and 7 percent.

Performance tests were then made with the same vehicle and carburetormodified by addition of the present invention; that is, a'device asshown in- FIGS. 1 through 4 was installed in each barrel of the twobarrel carburetor and tested as follows;

1. Under idling conditions, as expected, no significant change in COcontentoccurred; that is, the CO content was 0.2 percent. I

'2. Under steady state conditions, in the 25 to 35 miles-per-hourrange,the CO content dropped approximately one-half to about 1.25 1.5 percent.

3. Under high speed steady state conditions in the 60 to 70miles-per-hour range, a similar reduction -occurred, the CO contentbeing in the order of 0.5 percent.

4. Under conditions of rapid throttle acceleration and deceleration, agreater effective reduction of CO ranged between 2 and occurred; thatis, the CO content 3 percent.

It was also noted thatthe durations of the peak conditions resultingfrom acceleration and deceleration passage 12 is located perpendicularto the fuel supply I tube 4, or nearly so, and a concave reflectingsurface 19 is located in the wall of thetube 4, diametrically oppositefrom the outlet passage 12. The reflecting surface has the effect offurther intensifying the turbulence and increasing the intimacy ofmixture between the air and fuel.

Reference is now directed to FIGS. 6-and 7. The vor-.. tex whistle orvibration generator 9 is essentially the same as in the first describedstructure, except that the inlet ports 16 are located midway between thetop and bottom of the vortex chamber, and a pair of balls 20, havingrelatively high mass are free to rotate in the vortex chamber driven bythe entering air. The balls are dimensioned so that each prevents theother from closing the outlet 12. While two balls are preferred, threeor more could be used.

The balls, when rotated, produce a mechanical vibration which istransmitted by the walls of the vibration generator to the walls of thetube 4 and even to the walls of the venturi tube 3. This mechanicalvibration supplements the sonic vibration occurring in the air and fuel.Cylinders 21 may be substituted for the balls 20 and are dimensioned tobe positioned vertically or horizontally, the latter position beingindicated in FIG. 8

Reference is made to FIG. 9 which illustrates a portion of the vortexchamber wall 15 having undulations 22 forming striking shoulders toincrease the intensity of the mechanical vibrations.

Reference is now made to FIGS. and 11. The construction here illustratedincludes a rotor 23 having an eccentric mass or blade 24 driven by theentering air and carried on a shaft 25 journaled in the cap 14. Rotationof the blade 24 causes intense mechanical vibration.

Reference is now made to FIGS. 12 and 13. While any of the constructionsshown in FIGS. 6 through 11 may be substituted for the constructionshown in FIGS. 1 through 5, mechanical vibration may be furtherincreased by providing a boss 26 on the side of the venturi tube 3,opposite from the fuel supply tube 4, the boss having a hole therein toreceive the stem 11. With this arrangement, the outlet 12 dischargesdirectly into the main air stream, and the principal effect is toincrease mechanical vibration of the venturi tube.

The effect of such mechanical vibration is to induce the vibrations intoany liquid film on the surfaces of the venturi tube and its passageswith attendant improvement in atomization.

While particular embodiments of this invention have been shown anddescribed,'it is not intended to limit the same to the details of theconstructions set forth, but instead, the invention embraces suchchanges, modifications and equivalents of the various parts and theirrelationships as come within the purview of the appended claims.

I claim:

1. The combination with a carburetor having an air passage; means in theair passage, operable during flow of air through the air passage, toproduce a zone in the air passage lower than the normal pressure of airflowing in the air passage, and means defining a passageway forsupplying fuel to said zone for entrainment in the air flowing in theair passage, of a sonic generator, comprising:

a. means defining a vortex chamber;

b. at least one inlet exposed to the air flowing in the air passage anddirected tangentially into the vortex chamber to cause a turbulent airvortex in the cludes:

chamber;

c. and an outlet of reduced diameter directed axially from the vortexchamber into the fuel passageway adjacent said reduced pressure zonethereby to intensify the vortex turbulence of the air as it passes.through the outlet into the fuel passageway and to cause an intimateand turbulent premixing of air and fuel ior to dischar e int said educedpr ssure zon or entramme trn e arr owing m t e air passageway.

2. The combination of a carburetor and a sonic generator, as defined inclaim 1, which further ina. means defining a channel exposed to the airreceiving end of the inlet and directed upstream to convert a portion ofthe air velocity to increased pressure at the inlet thereby to increaseflow of air into the vortex chamber.

3. The combination of a carburetor and a sonic generator, as defined inclaim 1, wherein:

a. the discharge from the vortex whistle is transverse to the fuelpassageway and a reflecting surface is located at the far side of thepassageway to intensify the turbulent reaction between the air and thefuel.

4. A sonic generator, as defined in claim 1, wherein:

a. a rotatable mass is located in the vortex chamber to transmitmechanical vibration to the walls thereof.

5. A means of preparing a fuel-air mixture, comprisa. a tubularstructure forming an air passage;

b. a venturi disposed in the air passage and creating a zone of reducedpressure;

c. a fuel passage connected to the venturi and subject to the reducedpressure zone to. deliver fuel thereto;

. a vortex whistle including a vortex chamber having an inlet exposed toair in the inlet passage and an outlet directed into the fuel passageadjacent its connection with the venturi;

e. said vortex whistle being responsive to the pressure differentialbetween its inlet and outlet to' divert a portion of the air from theair passage to the fuel passage and generate turbulent vibrations in thediverted air, thereby to produce, with the fuel flowing in the fuelpassage, a turbulent fuel-air

1. The combination with a carburetor having an air passage; means in theair passage, operable during flow of air through the air passage, toproduce a zone in the air passage lower than the normal pressure of airflowing in the air passage, and means defining a passageway forsupplying fuel to said zone for entrainment in the air flowing in theair passage, of a sonic generator, comprising: a. means defining avortex chamber; b. at least one inlet exposed to the air flowing in theair passage and directed tangentially into the vortex chamber to cause aturbulent air vortex in the chamber; c. and an outlet of reduceddiameter directed axially from the vortex chamber into the fuelpassageway adjacent said reduced pressure zone thereby to intensify thevortex turbulence of the air as it passes through the outlet into thefuel passageway and to cause an intimate and turbulent premixing of airand fuel prior to discharge into said reduced pressure zone forentrainment in the air flowing in the air passageway.
 2. The combinationof a carburetor and a sonic generator, as defined in claim 1, whichfurther includes: a. means defining a channel exposed to the airreceiving end of the inlet and directed upstream to convert a portion ofthe air velocity to increased pressure at the inlet thereby to increaseflow of air into the vortex chamber.
 3. The combination of a carburetorand a sonic generator, as defined in claim 1, wherein: a. the dischargefrom the vortex whistle is transverse to the fuel passageway and areflecting surface is located at the far side of the passageway tointensify the turbulent reaction between the air and the fuel.
 4. Asonic generator, as defined in claim 1, wherein: a. a rotatable mass islocated in the vortex chamber to transmit mechanical vibration to thewalls thereof.
 5. A means of preparing a fuel-air mixture, comprising:a. a tubular structure forming an air passage; b. a venturi disposed inthe air passage and creating a zone of reduced pressure; c. a fuelpassage connected to the venturi and subject to the reduced pressurezone to deliver fuel thereto; d. a vortex whistle including a vortexchamber having an inlet exposed to air in the inlet passage and anoutlet directed into the fuel passage adjacent its connection with theventuri; e. said vortex whistle being responsive to the pressuredifferential between its inlet and outlet to divert a portion of the airfrom the air passage to the fuel passage and generate turbulentvibrations in the diverted air, thereby to produce, with the fuelflowing in the fuel passage, a turbulent fuel-air premixture fordelivery to the remaining air in the air passage through the zone ofreduced pressure created by the venturi.
 6. A means, as defined in claim5, wherein: a. a rotatable mass is located in the vortex chamber totransmit mechanical vibration to the walls thereof.
 7. A means, asdefined in claim 6, wherein: a. a second sonic generator is mounted onthe venturi to cause mechanical vibration of the walls thereof.